Trimming mechanism for sewing-machines



G. S. GATCHELL.

TBIMMING MECHANISM FOR SEWING MACHINES.

APPLICATION FILED NOV- 2!,1918- Patented Nov. 15, 1921.

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WITNESSES ATTORNEY G. S GAT'CHELL.

TBIMMING MECHANISM FOR SEWING MACHINES. APPLICATION FILED NOV.2I, 1918.

1,397,002. Patented Nov. 15,1921.

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' ATTORNEY NEED A tes T FFHC GEORGE S. GATCHELL, OF PiOSEL-LE PARK, NEW JERSEY, ASSIGNOR TO THE SING MANUFACTURING CGMIANY, A CORPGR-ATION OF NEW JERSEY,

TRIMIVEING MECHANISM FOR SEWING-MACHINES.

Specification of Letters Patent.

Patented N (W. 15, 1921.

Application filed November 21, 1918. Serial No. 263,454.

T 0 all to 710m it may concern Be it known that I, GEORGE S. GATOHELL, a citizen of the United States, residing at Roselle Park, in the county of Union and State of New Jersey, have invented certam new and useful Improvements in Trimming Mechanisms for Sewing /Iachines, of which the following is a specification, reference being had therein to the accompanylng drawings.

This invention relates to sewing machines and has for an object to provide fabric trunming mechanism therefor which may be instantly thrown into or out of operation with.

the least possible effort on the part of the operator, and which is of simple and durable construction.

A further object of the invention is to pro vide a throw-out trimmer of the type having cutting meansv operating upon tip-turned marginal portions of material passing 1nto the slot between the toes of a bifurcated presser-foot; the trimming mechanism being so constructed and arranged as to close the upper side of the slot when said mechanism is thrown out of operation, thereby preventing the fabric from riding or curling up above the slot, when it is desired to sew without trimming.

Still further, the invention has for an object to provide a cylinder bed sewing machine with a horizontal trimmer whlch may be instantly thrown into or out of operation, 2'. 0., from operative to inoperative position, or vice-versa, by a single movement of the operators hand.

For the purpose of the present disclosure the invention will be described as embodied in a machine constructed substantially in accordance with the disclosure in my copending application Serial No. 185,446, filed- August 10, 1917. The improved trimming mechanism is of the type disclosed in my said copending application but has been modified in certain import-ant particulars. In the present instance the lever carrying the movable trimmer-blade is replaced by two levers, one of which is a constantly vibrating actuator lever and the other of which carries the movable trimmer-blade and maybe termed the trimmer-lever. A

manually controlled coupling device is provided for establishing and interrupting operative connection between the actuator and trimmer-levers. The coupling devlce may comprise a spring-pressed latch-lever fulcrumed on the trimmer-lever and formed with a tooth adapted to enter a complemental slot in the actuator-lever.

An important feature of the present construction is the means for detaining the latch-lever in ineffective position and the trimmer-lever in or near the position which it occupies at the end of a cutting stroke, so that the trimmerdolade will close the upper side of the slot between the toes of the presser-foot.

Another important feature of the present invention is the construction and relative arrangement of the latch-lever, whereby it may be shifted in one direction to unlock the trimmer-lever from the actuator and move said lever to inoperative position; said latch operating further to detain the trimmer-lever in inactive position. The trimmer-lever may be instantly returned to op erative position by a single movement of the operators hand, in which position the operative connection between the actuator and trimmer-levers is automatically restored as the tooth on the spring-pressed latch-lever drops into the slot in the actuator.

In the accompanying drawings, Figure 1 is a side elevation of a machine embodying the invention. Fig. 2 is a front end elevation of the machine. Figs. 3 and 4 are plan views of the trimmer mechanism, showing the trimmer-lever in operative and inoperativepositions, respectively. Fig. 5 is a vertical cross section through the presser-foot and throat-plate, showing the relative arrangement of the trimmer and ledger-blades.

In the preferred embodiment of the invention, as illustrated, the machine frame comprises a base 1 from which rises the standard 52 carrying the bracket arm 3 terminating in the hollow-head lbeneath which arm and head is supported the cylinder-bed or work-supporting arm joined at its rearward end to the standard 2 at an elevation above the base 1. Journaled within and transversely of the standard 2 is the mainshaft 6 carrying the usual handand beltwheel 7 and formed with a crank 8 which is operatively connected by means of the pitman 9 to the oscillatory needle-driving shaft 10 extending within and longitudinally of the bracket-arm The needle-driving shaft 10 has fixed to its forward end a crankarm 11 which is connected by means of the usual link 12 to the reciprocating needle-bar 13 journaled in the head 4 and carrying, in the present instance, four eye-pointed needles n cooperating with the looper 8 in a manner well understood and fully set forth in my said copending application. Fixed to the oscillatory needle-driving shaft 10 is a bevel-gear 14 meshing with a similar gear 15 fixed to the upper end of a short vertical shaft 17 journaled within a suitable bearing boss 18 at the under side of the bracket-arm 3. At its lower end the shaft 17 is provided with a crank-pin 19 entering the slide-block 20 which is embraced by the forward extremity of one arm 21 of the trimmer actuator lever fulcrumed on the vertical stud-pin 22 fixed within a suitable socket at the under side of the bracket-arm 3 closely in rear of the head 4, as shown in Fig. 1. The other arm 23 of the trimmer actuator lever is formed at its extremity with a notch 24.

F ulcrumed upon the studpin 22 for movement independently of the lever 21, 23, is the trimmer-lever 25 which at its forward end is provided with a downward extension 26 and two bearing lugs 27, 27, in which is journa'led a slide-rod 28 carrying at its lower end a clamp-block 29 in which the trimmerblade 30 is mounted. The trimmer-blade 3O cooperates in the usual manner, as disclosed in my said copending application, with the ledger-blade 31 to trim off the up-turned marginal portions of material 32, Fig. 5, as said marginal portions pass into the slot between the toes 33, 33, of the bifurcated presser-foot 34; I

Pivotally mounted upon the trimmer-arm 25 by means of the screw 35 is a manually controlled three-armed latch-lever 36 the rearwardly extending arm 37 of which is formed with a tooth 38 adapted to enter the slot 24 at the extremity of the arm 23 of the actuator lever and couple the latter to the trimmer-lever. The tooth 38 is tapered slightly toward its free end and the slot 24 is correspondingly tapered so that the latch 37 will operate to rigidly connect the trimmer and actuator arms and prevent the appearance of lost motion at this point. The forwardly'extending arm 39 of the latchlerer 36 is in the form of a finger-piece and is pressed outwardly by means of the spring 40 mounted in a suitable socket in the trimmer-lever 25 as shown in Figs. 3 and 4; spring 40 operating to yieldingly shift the tooth 38 into engagement with the slot 24 in the actuator.

When it is desired to throw the trimmer out of operation the operator merely pushes the finger-piece 39 toward the left, Fig. 3, whereupon the tooth 38 will be withdrawn from the slot 24 and the trimmer-arm 25 shifted to its inactive position as shown in Fig. 4. In this position the pointed extremity of the third arm 41 of the latch-lever 36 will be yieldingly pressed into a notch 42 at the extremity of a stop 43 fixedly secured to the head 4 and thus virtually constituting a part of the frame of the machine. In the particular embodiment shown and described the notch 42 is V-sha-ped and operates to eject the extremity of the arm 41 when the trimmer-arm 25 or its extension 26 is grasped by the operator and forcibly shifted toward the right into operative position. Upon reaching operative position the tooth 38 will automatically snap into the slot 24 and restore the operative connection of the trimmer-arm 25 .with its actuating means.

The invention is not to be understood as limited to the exact form and arrangement of the parts shown and described, as the form disclosed is obviously susceptible of material modification within the scope of the invention defined in the appended claims.

Having thus set forth the nature of the invention, what I claim herein is- 1. Trimming mechanism for sewing machines, comprising a frame, a trimmer blade carrying arm movable from operative to inoperative position, an actuator, a coupling element carried by said trimmer blade carrying arm for operativelyconnecting it with said actuator, and means carried by the frame and cooperating with said coupling element for retaining said trimmer blade carrying arm in inoperative position.

2. In a sewing machine, in combination, a presser-foot having spaced toe-portions defining a slot into. which up-turned marginal portions of material are adapted to pass, trimming mechanism including a trimmerblade adapted to trim off said up-turned marginal portions of material, a constantly operating actuator, a releasable connection between said trimmer-blade and actuator, and means for detaining said trimmer-blade in inoperative position covering the slot in said presser-foot when said blade is released from its actuator.

3. A sewing machine comprising, a frame formed with a standard, a bracket-arm, and a tubular work-supporting arm free at one end and at its opposite end joined to said standard, stitch-forming and feeding mechanisms incorporated in said frame, trimmer and actuator arms fulcrumed on said bracket-arm for movement independently of one another, and a releasable coupling device for said arms including a finger-piece extended forwardly in a direction substantially parallel with said bracket and workarms at one side of the stitching point.

4. A trimming device for sewing machines, comprising a trimmer-blade supporting member movable from operative to inoperative position and vice versa, an actuator, and a coupling device including a manually controlled element carried by said trimmer-blade supporting member and acting when shifted in one direction only to first 'uncouple said actuator and member and then shift the latter to inoperative position.

5. A trimming device for sewing machines, comprising a trimmer-blade supporting member movable from operative to inoperative position and vice versa, an actuator, a coupling device including a manually controlled element carried by said trimmerblade supporting member and acting when shifted in one direction only to first, uncouple said actuator and member and then shift the latter to inoperative position, and means cooperating with said coupling device for retaining said member in inoperative position.

6. Trimming mechanism for sewing machines comprising, a constantly vibrating arm, a trimmer-blade carrying arm shiftable from operative to inoperative position, a releasable coupling device carried by said trimmer-blade carrying arm for rigidly connecting said arms together, and a stationary element, said coupling device comprising a three-armed latch, one of said arms affording a finger-piece, another of said arms operating to transmit power to the trimmerblade, and the third arm adapted to cooperate at times with said stationary element to retain the trimmer-blade carrying arm in inoperative position.

7. In a sewing machine, a frame including a work-supporting arm, and an overhanging bracket-arm, stitch-forming mechanism incorporated in said frame and including a reciprocating needle, a trimmer-blade sup porting member carried by said bracket-arm and adapted to oscillate about an axis extending in the same general direction as the direction of reciprocation of said needle and to be shifted into and out of operative position, an oscillatory actuating element, and a spring-pressed latch pivoted to said trimmerblade supporting member and operating automatically when said member is moved to operative position to couple said member to said actuating element.

8. In a sewing machine, a frame including a woi'lesupporting arm, and an overhanging bracket-arm, stitch-forming mechanism incorporated in said frame and including a reciprocating needle, a trimmer-blade supporting member carried by said bracket-arm and adapted to oscillate about an axis extending in the same general direction as the direction of reciprocation of said needle and to be shifted into and out of operative position, an oscillatory actuating element, a spring-pressed latch pivoted to said trimmerblade supporting member and operating automatically when said member is moved to operative position to couple said member 7 to said actuating element, said latch being also adapted to cooperate with the frame of the machine to retain the trimmer-blade supporting member in inoperative position.

9. In a sewing machine, in combination, a frame having a tubular work-supporting arm and an overhanging bracket-arm, stitchforming mechanism including a reciprocating needle and a needle-operating shaft extending lengthwise of the bracket-arm, feeding mechanism, a presser-foot having a slot into which up-turned marginal portions of material are adapted to pass, a trimmer mounted for oscillation about a vertical axis, a trimmer-blade carried by said trimmerarm and operating horizontally upon said up-turned marginal portions of material, a rock-arm operatively connected to said trimmer-arm and adapted to oscillate about said vertical axis at a level above the trimmerarm, and means driven by said needle-operating shaft for oscillating said rock-arm, the train of connections for operating the trimmer-arm including a manually controlled disconnectible connection, whereby the trimmer-arm may be thrown into and out of action at the will of the operator.

10. In a sewing machine, in combination, a frame including work-supporting and bracket-arms, a reciprocating needle-bar, a looper, a feed, a presser-foot having spaced toes into which upturned marginal portions of material are adapted to pass, a pair of lever-arms sustained by said braclret'for independent movement about an axis parallel to said needle-bar, a trimmer-blade connected to one of said arms and adapted to operate horizontally upon said upturned marginal portions of material, an actuator connected to the other of said arms, and readily releasable means for coupling said arms together.

In testimony whereof, I have signed my name to this specification.

GEQRGE S. GAICHELL. 

